2BWise

I see. It sounded as though you were removing hardware from the system. Part of the problem was your description of; PSM charge pump. PSM and ABS share the same hardware, so same pump motor and same controller. That connector isn't by chance the connector for yaw rate sensor and steering angle is it? The only hardware available that ABS does not directly use is these two sensors, so by disconnecting them you'd fault the PSM system and leave ABS able to still run. Although ABS is still functional it is not the same algorithm as when PSM is also available. It is in a reduced operating mode.

When you normally are driving on track are you using ABS?

wanna911

I don't know what it is I just know that the annoying PSM goes away and ABS stays with it on. My braking distances have not gotten any longer since I disconnected that though, but ABS does seem to engage sooner. A trade I'm willing to make (as long as it's not causing this issue, which I don't think it is).

I use ABS but mostly in the same turns, 1 (occasionally), 3, 10a at Road Atlanta. 1, 5, 7b at Barber. 1, 11, 14 at CMP.

jrgordonsenior

Sorry I can't tell from that photo. They're easy to find where they bolt to the unibody frame rail....

924RACR

Um... yeah, what Bill said.

ABS and PSM are simply two different faces of the same body - they are indeed tied together. If you have PSM failed (not merely turned off, but failed via a sensor or the like) then you likely have reduced ABS function. I would certainly not trust it on track in heavy usage.

Hard to say from the pic, and I'm a bit less familiar with this particular system, but it seems like you're probably disconnecting the ABS motor...

wanna911

I've probably done 15 events since last March. Any insight as to why it would take until the 14th one to demonstrate problems?

Nordschleife

Why muck around with the PSM/ABS sub-systerms?

The best drivers I know are supremely indifferent as to whether the PSM is active or not. PSM intervenes when there is a potentially unsafe situation and the driver does nothing about it ( sorry, a boot full of welly and all crossed up isn't one of the acceptable solutions).

Consider the PSM as a slightly autistic driving coach, not big on conversation but interventionist when you aren't driving properly. You will need quick and tidy hands (and thoughtful feet) to prevent its intervention, but that's what you are working on.

I have driven with successful racers who hate ESP/PSM/whatever, however their technique tends towards the colourful end of the spectrum. Racers and former racers who also work on car development have few problems with ESP.

For some reason, when I take US based folk around the 'Ring, they find it an irresistable idea to turn the ESP on and off as I drive. I don't know why, if they want the adrenalin ride, all they have to do is ask, oversteer is easily arranged.

R+C

wanna911

It's personal preference, I choose not to have unpredictable and hindering electronics interfering with my control of the car. PSM off is just plain annoying and unpredictable and on is a waste of time especially if your car has a race set up and the system is designed for street settings.

I'd rather not get into a discussion about driving with or without PSM. It's not an option for me and for all the cars that have PSM, there are a ton that had it and race without it and without ABS problems, I just want to find out how and if my problems are sensor related, as they seem to be. I'm inclined to believe I would have had this problem with or without PSM connected, should have tried it the other week, but did not want to risk a third on track ABS failure.

924RACR

Very possibly seat time. Though I'm still not certain exactly how you disabled the PSM system (due to terminology differences), so I'm not quite certain just how much ABS function you can expect to still have. Normally one would just disconnect the steering angle or yaw rate/combo sensor, not the pump.

Of course, you could just complete the cycle and learn to modulate the brakes, too... j/k